WO2001033809A1

WO2001033809A1 - Communication apparatus and communication method

Info

Publication number: WO2001033809A1
Application number: PCT/JP2000/007536
Authority: WO
Inventors: Yoji Yokoyama
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 1999-10-29
Filing date: 2000-10-27
Publication date: 2001-05-10
Also published as: AU7959700A; KR100402566B1; CN1327668A; JP2001127824A; JP3938824B2; KR20010093234A; US7356024B1; CN1154330C; EP1143684A1; EP1143684A4

Abstract

A predetermined table where pieces of control data of each type (each message unit) are grouped and correlated with one another is stored in a correlation storage section (105). A control data synchronizing section (104) accumulates inputted control data sequentially in a control data accumulating section (106). The control data synchronizing section (104) groups a plurality of pieces of control data, correlates them with one another with reference to the table stored in the correlation storing section (105), and accumulates them. The pieces of control data are multiplexed through these operations and handled as a piece of data in units of a group. A control data processing section (107) generates the control data multiplexed for each group as a packet and transmits it to the communication party.

Description

Description Communication device and communication method

The present invention relates to a communication device and a communication method, and more particularly to a communication device and a communication method used for multimedia communication in an ITU (International Telecommunication Union). Background art

Conventionally, in digital communication, a moving image signal, an audio signal, and the like are compressed by a compression method of a predetermined standard, an image stream, an audio stream, and the like obtained by compression are multiplexed. Multimedia communication is performed by transmission.

Before the start of transmission of stream data, control data is exchanged between communication terminals with respect to a moving picture coding method, a sound coding method, a data transmission method, or the like. Then, after it is determined how to perform communication within the range of the capabilities of the communication terminal, resources necessary for communication are prepared, and the transmission of the stream data is not performed until these are completed. Be started.

Currently, ITU-T standard H.245 (hereinafter referred to as II.245 standard) is used for control data exchange performed before the start of stream data transmission. This standard is a communication control protocol developed for AV multimedia communication using packet multiplexing, and is used by many multimedia communication terminals.

According to the H.245 standard, after the start of communication, the communication terminals first exchange control data regarding the capabilities of the communication terminals and exchange acknowledgment signals for the control data, and determine the communication terminal types and the superiority of the communication terminals. Exchange of information to determine (this Called "transmission start phase 1". ) Is performed. In the transmission start phase 1, control data and the acknowledgment signal for the control data are exchanged by the number of media (audio, video, etc.). After the transmission start phase 1, the capabilities of the sending and receiving terminals are determined, and a logical connection is established for each medium (this is called “transmission start phase 2”). After the end of transmission start phase 2, multiplexing information for packet multiplexing of data and an acknowledgment signal for the multiplexed information are exchanged (this is called “transmission start phase 3”). The transmission of the stream is started only after the processing of the transmission start phases 1 to 3 has been completed.

However, according to the H.245 standard, a communication terminal sends control data to a communication partner, obtains an acknowledgment signal (ACK, NACK) of the control data from the communication partner, and then transmits the next control data. The confirmation-type procedure is as follows. With such a procedural configuration, reliable transmission of control data is guaranteed, but the longer the number of control data that must be exchanged before the start of stream data transmission, the longer the time before the start of stream data transmission. Is required. In general, in the H.245 standard, transmission of stream data is started after about 20 pieces of control data are exchanged. Hereinafter, this problem will be specifically described with reference to FIG.

FIG. 1 is a sequence diagram showing how a communication terminal equipped with a conventional communication device exchanges control data. In FIG. 1, the timing (hereinafter, abbreviated as “t”) 11 and t 21, the communication terminals A and B send control data A-1 and control data B-1 to the communication partner, respectively. Send In the following description, for convenience of explanation, the operation will be focused on the operation of communication terminal A, and the problem will be described.

After transmitting control data A-1, communication terminal A generates control data A-2 to be transmitted next. When receiving the control data A_1 at t22, the communication terminal B returns a reception confirmation signal 1 to the communication terminal A. At t 1 3 acknowledgment signal 1 is received. Communication terminal A can transmit the next data, and transmits a response to the inquiry about control data B-1 received at t 12 to communication terminal B at t 13 . Here, it is assumed that the communication terminal A has already completed the preparation for transmitting the control data A-2 transmitted next from the communication terminal A at t13.

Upon receiving the response data at t 23, communication terminal B returns reception acknowledgment signal 2 to communication terminal A. Communication terminal A, which has received the acknowledgment signal 2 at t 1 4, can transmit the next data. Transmit at t1 4.

As described above, according to the H.245 standard, the communication terminal A cannot transmit the control data A-2 until it receives the acknowledgment signal 2, and thus transmits the control data A-2. The waiting time shown in Fig. 1 occurs. The frequency of occurrence of such a waiting time increases as the number of control data that must be exchanged before the start of stream data transmission increases. Therefore, as the number of control data increases, it takes a longer time to start transmission of stream data. Disclosure of the invention

An object of the present invention is to provide a communication device and a communication method that can reduce a waiting time for transmission of control data and reduce a transmission start delay of stream data.

In order to achieve the above object, the present invention reduces the number of exchanges of control data by multiplexing and transmitting a plurality of control data that can be transmitted without waiting for response data from a communication partner as one multiplex unit. I made it. BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows how a communication terminal equipped with a conventional communication device exchanges control data. FIG.

FIG. 2 is a main part block diagram showing a schematic configuration of the communication device according to Embodiment 1 of the present invention.

FIG. 3 is a diagram showing an example of table contents stored in the association storage unit of the communication device according to Embodiment 1 of the present invention.

FIG. 4 is a sequence diagram showing a state in which a communication terminal equipped with the communication device according to Embodiment 1 of the present invention exchanges control data.

FIG. 5 is a main part block diagram showing another schematic configuration of the communication device according to Embodiment 1 of the present invention.

FIG. 6 is a main part block diagram showing a schematic configuration of a communication device according to Embodiment 2 of the present invention.

FIG. 7 is a sequence diagram showing a state in which a communication terminal equipped with a communication device according to Embodiment 2 of the present invention exchanges control data.

FIG. 8 is a main part block diagram showing a schematic configuration of a communication device according to Embodiment 3 of the present invention.

FIG. 9 is a sequence diagram showing a situation where a communication terminal equipped with a communication device according to Embodiment 3 of the present invention performs control data exchange. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)

The communication device and the communication method according to the first embodiment of the present invention relate a plurality of control data that can be transmitted collectively and a plurality of control data generated asynchronously, and a plurality of control data according to the association. It is multiplexed and transmitted in one bucket.

Hereinafter, the communication device and the communication method according to Embodiment 1 of the present invention will be described using FIG. FIG. 2 is a schematic diagram of a communication device according to Embodiment 1 of the present invention. It is a principal part block diagram which shows schematic structure.

The control data management unit 102 that has been notified of the start of communication from the terminal control unit 101 outputs a control data transmission instruction to the control data transmission unit 103. The control data transmitting unit 103 that has received the transmission instruction generates transmission control data and outputs it to the control data synchronizing unit 104.

When there is a control data that needs to be transmitted continuously, the control data management unit 102 outputs a transmission instruction to the control data transmission unit 103 again. As a result, the control data transmitting section 103 again generates transmission control data and outputs it to the control data synchronizing section 104.

The control data synchronization unit 104 multiplexes a plurality of transmission control data by operating together with the association storage unit 105 and the control data storage unit 106. The multiplexed transmission control data is output to the control data management unit 102. The multiplexing operation will be described later.

The data output to the control data management unit 102 is output to the control data processing unit 107, and is temporarily stored in the multiplexed data storage unit 108. When the control data processor 107 detects the reception of the reception confirmation signal transmitted from the communication partner, the control data processor 107 extracts the multiplexed transmission control data from the multiplexed data storage unit 108, An error detection code and the like are added to generate a single bucket. Therefore, this one packet includes a plurality of transmission control data. The generated packet is subjected to predetermined wireless processing after adding header information and the like in the transmission section 109 and transmitted to the communication partner via the antenna 110.

On the other hand, the control data received via the antenna 110 is subjected to predetermined radio processing in the transmission unit 109, and then output to the control data processing unit 107. The control data processing unit 107 performs processing such as error detection on the reception control data, and outputs a reception acknowledgment signal to the transmission unit 109 if reception is correct, and manages the reception control data in control data management. Output to section 102. The acknowledgment signal is After a predetermined wireless process is performed in the transmitting unit 109, the signal is transmitted to the communication partner via the antenna 110.

The control data management unit 102 outputs the reception control data output from the control data processing unit 107 to the control data reception unit 111. The control data receiving unit 111 analyzes the contents of the reception control data, generates a response data if a response to the inquiry about the reception control data is necessary, and outputs the response data to the control data synchronization unit 104. . In the following description, the transmission control data generated by the control data transmission unit 103 and the response data generated by the control data reception unit 111 are collectively referred to as “control data”. The data in which a plurality of control data are multiplexed is called "multiplex control data".

The control data synchronization unit 104 operates in conjunction with the association storage unit 105 and the control data storage unit 106 to multiply response data and transmission control data. The multiplexed data is output to the control data management unit 102. The multiplexing operation will be described later. Hereinafter, the processing up to the transmission of the multiplexed data is the same as described above, and the description is omitted.

As described above, between the communication terminals equipped with the communication device, after the exchange of the control data in each transmission start phase, transmission of stream data such as audio data, image data, etc. is started. That is, after the exchange of the control data is completed, the terminal control unit 101 outputs an activation signal to the user data processing unit 112, whereby the user data processing unit 112 is activated.

The user data overnight processing unit 112 performs predetermined processing (for example, arithmetic processing of the MPEG-4 system) on user data such as audio and images input via the input / output terminal 113, After generating the transmission stream data and outputting it to the transmission unit 109, the user data processing unit 112 performs predetermined processing on the reception stream data output from the transmission unit 109, and then performs input processing. Output to other devices via output terminals 113.

Next, the control data synchronization unit 104, the association storage unit 105, and the control data The operation in which the evening storage unit 106 multiplexes control data will be described.

The association storage unit 105 stores a predetermined table as shown in FIG. 3, in which each control data is grouped for each type (each message unit) and associated. FIG. 3 is a diagram showing an example of table contents stored in the association storage unit of the communication device according to Embodiment 1 of the present invention.

Here, each message belonging to one group in the table shown in FIG. 3 is a message that can be transmitted collectively to a communication partner. That is, since the "terminal capability information exchange message" is a message that can be transmitted without waiting for the response data from the communication partner to the "mass evening slave decision message", the "mass evening slave decision message" And the "terminal capability information exchange message" can be transmitted together to the communication partner. Therefore, the “master / slave decision message” and the “terminal capability information exchange message” are grouped together.

On the other hand, since the capabilities of the communication partner terminal cannot be known without waiting for the response data from the communication partner to the “terminal capability information exchange message”, the “terminal capability information exchange message” and the “logical channel opening message” Cannot be sent to the other party at once. Therefore, the "terminal capability information exchange message" and the "logical channel establishment message" are separate groups. The stored contents have a configuration that can be changed adaptively according to the communication conditions. In other words, when communication without voice is performed, there is no need to open a logical channel for voice. Therefore, the table shown in Fig. 3 is the same as the table in which “Logic channel opened (voice)” is omitted from group 2. Become.

The control data synchronization unit 104 sequentially stores the input control data in the control data storage unit 106. When accumulating the control data, the control data synchronization unit 104 refers to the table shown in FIG. 3 stored in the association storage unit 105 and stores the control data to which control data belongs. Judge whether it is data. Then, the control data synchronization unit 104 associates a plurality of control data for each group, Manage as one data per group. By such an operation, a plurality of control data are multiplexed for each group, and each group is treated as one data unit.

Specifically, for example, when the “master slave determination message” is input to the control data synchronization unit 104, the control data synchronization unit 104 sets the “master slave determination message” to the group 1 Is determined to belong to In addition, since the control data synchronization section 104 has a “terminal capability information exchange message” after the “master / slave determination message” in Group 1, the “terminal capability information exchange message” follows the “master / slave determination message”. It can be seen that "exchange message" is continuously input. Therefore, in this case, the control data synchronizing section 104 accumulates the “mass slave decision message” in the control data accumulating section 106 as a control data belonging to group 1.

When the input control data is the last data of each group, the control data synchronization unit 104 stores the control data in the control data storage unit 106, and then stores The stored and multiplexed control data is taken out as one data from the control data storage unit 106 and output to the control data management unit 102. After the output, the control data synchronization unit 104 clears the control data accumulation unit 106.

Specifically, for example, when the “terminal capability information exchange message” is input to the control data synchronization unit 104, the “terminal capability information exchange message” in group 1 is the last control data exchange message. Therefore, after storing the “terminal capability information exchange message” in the control data storage unit 106, the control data synchronization unit 104 transmits the “mass evening slave determination message” and the “terminal capability information exchange message”. The message is taken out of the control data storage unit 106 as one data and output to the control data management unit 102.

The multiplexed control data output to the control data management unit 102 is output to the control data processing unit 107 and temporarily stored in the multiplexed data storage unit 108. And Each time the control data processing unit 107 detects the reception of the reception confirmation signal transmitted from the communication partner, the control data processing unit 107 sequentially extracts the multiplexed control data from the child data storage unit 108, and extracts the sequence number, the error detection code, and the like. Add them to generate one packet for each group. Therefore, this one packet includes a plurality of transmission control data. The generated packet is subjected to predetermined radio processing in the transmission unit 109 after header information and the like is added thereto, and is transmitted to the communication partner through the antenna 110.

Next, the manner in which a communication terminal equipped with a communication device having the above configuration exchanges control data will be described. FIG. 4 is a sequence diagram showing a state in which a communication terminal equipped with the communication device according to Embodiment 1 of the present invention exchanges control data.

In FIG. 4, at timings (hereinafter abbreviated as “t”) 11 and t 21, communication terminals A and B send control data A-1 and control data B-1 to a communication partner, respectively. Send The following description focuses on the operation of the communication terminal A for convenience of description.

The communication terminal A generates, in the control data receiving unit 111, response data to the inquiry about the control data B_1 received at t12. This response data is stored in the control data storage unit 106.

After transmitting the control data A-1, the communication terminal A generates control data A-2 to be transmitted next in the control data transmitting unit 103. The control data A-2 is stored in the control data storage unit 106. As a result, the response data and the control data A-2 are multiplexed.

Here, it is assumed that the control data A-1 and the control data A-2 are control data belonging to different groups. The response data and the control data A-2 are control data belonging to the same group.

When communication terminal B receives control data A-1 at t22, communication terminal B returns reception acknowledgment signal 1 to communication terminal A. Communication terminal A that has received the acknowledgment signal 1 at t 1 3 Since the next data can be transmitted, the control data processing unit 107 combines the multiplexed response data and control data A-2 into one packet, and t 13 To send to communication terminal B. In this way, by multiplexing a plurality of control data and transmitting them as one bucket, the number of transmissions of the control data can be reduced. Also, since communication terminal A multiplexes response data and control data A-2 and transmits them in one packet, the waiting time conventionally caused as shown in FIG. 1 can be reduced.

Then, upon receiving the packet including the response data and the control data A-2, the communication terminal B transmits a reception confirmation signal 2 to the communication terminal A at t23. The acknowledgment signal 2 is received by the communication terminal A at t14.

The communication device according to the present embodiment may have a configuration as shown in FIG. FIG. 5 is a main block diagram showing another schematic configuration of the communication device according to Embodiment 1 of the present invention. In the communication device shown in FIG. 5, the control data management unit 102 refers to the association storage unit 105, and sends a control data input / output instruction signal to the control data storage unit 106. Output to control data synchronization section 104. The control data synchronizing unit 104 accumulates the input control data in the control data accumulating unit 106 according to the instruction signal, or stores the accumulated multiplexed control data in the control data accumulating unit 104. Extract from 6 as 1 data.

As described above, according to the communication apparatus and the communication method according to the present embodiment, a plurality of control data that can be transmitted collectively and a plurality of control data that occurs asynchronously are associated with each other, and a plurality of control data are associated with the association. Data is multiplexed and transmitted as one bucket. As a result, the waiting time for transmitting control data can be reduced, and the number of control signal exchanges can be reduced. Therefore, it is possible to reduce the delay in starting the transmission of stream data due to the waiting time.

(Embodiment 2) The communication apparatus and the communication method according to the present embodiment differ from the first embodiment in that control data multiplexed according to association is further multiplexed and transmitted as one packet.

Hereinafter, a communication device and a communication method according to Embodiment 2 of the present invention will be described using FIG. 6 and FIG. FIG. 6 is a main block diagram illustrating a schematic configuration of a communication device according to Embodiment 2 of the present invention. FIG. 7 is a block diagram illustrating a communication terminal including a communication device according to Embodiment 2 of the present invention. FIG. 7 is a sequence diagram showing how control data is exchanged. In FIG. 6, the same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description is omitted.

Since the control data processing unit 501 cannot transmit the multiplexed control data until the reception confirmation signal transmitted from the communication partner is received, as shown in FIG. During this time, the multiplexed control data output from the control data management unit 102 is sequentially stored in the multiplexed data storage unit 108. Here, for example, it is assumed that two multiplex control data of multiplex control data 1 and multiplex control data 2 are accumulated. As a result, a plurality of control data multiplexed in groups are further multiplexed in a plurality of groups.

When detecting the reception of the acknowledgment signal at t13 shown in FIG. 7, the control data processing section 501 receives all multiplexed control data (multiplexed control data 1 and multiplexed control data 2) accumulated up to that point. Is extracted from the multiplexed data storage unit 108, a sequence number, an error detection code, and the like are added to generate a single bucket and output to the transmission unit 108. As a result, the control data multiplexed between a plurality of groups is transmitted to the communication partner as one packet. After the output, the control data processing unit 501 clears the multiplexed data storage unit 108.

As described above, according to the communication device and the communication method according to the present embodiment, control data multiplexed according to the association is further multiplexed and transmitted as one packet. By this means, the number of control signal exchanges can be further reduced as compared to Embodiment 1, and the transmission efficiency of control signals can be increased. Yo Thus, the time required for starting the transmission of stream data can be further reduced.

(Embodiment 3)

The communication apparatus and the communication method according to the present embodiment are different from the second embodiment in that control data multiplexed between a plurality of groups is not transmitted at the time of receiving a reception confirmation signal, but at predetermined time intervals. This is the point of transmission.

Hereinafter, a communication device and a communication method according to Embodiment 3 of the present invention will be described using FIG. 8 and FIG. FIG. 8 is a main block diagram illustrating a schematic configuration of a communication device according to Embodiment 3 of the present invention. FIG. 9 is a block diagram illustrating a communication terminal including a communication device according to Embodiment 3 of the present invention. FIG. 7 is a sequence diagram showing how control data is exchanged. In FIG. 8, the same components as those of the second embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

Depending on the timing of multiplex control data generation, such as when multiplex control data is generated frequently, immediately after the control data processing unit 701 receives the acknowledgment signal, the control data management unit 102 It is conceivable that the next multiplex control data is output to the unit 701. In this case, the transmission efficiency can be improved by transmitting in a single bucket including the multiplex control data output immediately after the reception confirmation signal is received. Therefore, in the communication device and the communication method according to the present embodiment, one bucket is generated including the multiplex control data output immediately after receiving the reception confirmation signal.

As shown in FIG. 9, the control data processing unit 701 stores the multiplex control data 1 in the multiplex data storage unit 108 when the multiplex control data 1, which is the first multiplex control data, is input. At the same time, the timer 702 is started.

Until the timer 702 expires, the control data processor 701 multiplexes the multiplexed control data output from the control data manager 102 as shown in FIG. The data is sequentially stored in the storage unit 108. Now, here, for example, It is assumed that three multiplex control data of multiplex control data 1 to 3 are accumulated from the start of 2 to the expiration.

After receiving the reception acknowledgment signal at t13 shown in Fig. 9, the control data processing unit 701, when the timer 702 expires at t14, all the multiplexed control data accumulated so far. The multiplexed control data 1 to 3 are taken out from the multiplexed data storage unit 108, a sequence number, an error detection code, and the like are added to the multiplexed data to generate a single bucket and output to the transmission unit 109. After outputting, the control data processing unit 7 0 1 serves to Kuria multiple data storage unit 1 0 8, _t Note restart the evening timer 7 0 2, the predetermined time to be set evening now 7 0 2, multiple Consider the control data generation timing, etc., and set the transmission efficiency to be the highest.

As described above, according to the communication device and the communication method according to the present embodiment, control data multiplexed between a plurality of groups is transmitted at a predetermined time interval instead of being transmitted at the time of receiving a reception confirmation signal. . This makes it possible to further reduce the number of control signal exchanges and increase the control signal transmission efficiency, as compared with the second embodiment, when multiplex control data is frequently generated. Therefore, the time required until the start of stream data transmission can be further reduced.

In the first to third embodiments, the case where the transmission path is wireless has been described. However, the present invention is not limited to this, and the transmission path may be wired.

In addition, if an error occurs during the transmission of control data, it is necessary to retransmit the control data in which the error has occurred, so multiple control data are multiplexed and transmitted in one bucket. Modes 1 to 3 are particularly effective in communication systems in which errors are likely to occur during transmission. In addition, by using the communication apparatus according to Embodiments 1 to 3 on both the transmitting side and the receiving side, the waiting time is similarly reduced on both sides, and there is no shift in the operation timing between both sides, so that real-time Two-way communication becomes possible.

In addition, the first to third embodiments can be realized by software. is there. It is also possible to store the software on a storage medium and read and execute it on a computer.

As described above, according to the present invention, to reduce the between waiting time concerning the transmission of control data, _t herein can reduce the transmission start delay of the stream data Heisei 1 1 October 2000 2 It is based on Japanese Patent Application No. 11-309005 filed on the 9th. All this content is included here. Industrial applicability

The present invention can be applied to a base station device and a communication terminal device used in a wireless communication system.

Claims

The scope of the claims

1. A storage unit that accumulates multiple control data in multiple units ^, and multiple control data, in which multiple control data are multiplexed in multiple units after receiving a reception confirmation signal from the communication partner, as one transmission unit A transmitter for transmitting, and a communication device comprising:

2. The communication device according to claim 1, wherein the storage stores information relating a plurality of control data stored as one multiplex unit.

3. A multiplexor for sequentially storing a plurality of multiplexed control data and further multiplexing a plurality of multiplexed control data, wherein the transmitter transmits the plurality of multiplexed control data as one transmission unit. The communication device as described.

4. The communication device according to claim 3, further comprising a timer for repeatedly measuring a predetermined time, wherein the transmitter transmits a plurality of multiplex control data as one transmission unit at each predetermined time.

5. A communication terminal device equipped with a communication device, wherein the communication device stores a plurality of control data for each multiplexing unit and a plurality of control data after receiving a reception confirmation signal from a communication partner. And a transmitter for transmitting, as one transmission unit, multiplexed control data obtained by multiplexing for each multiplexing unit.

6. A base station device equipped with a communication device, wherein the communication device stores a plurality of control data for each multiplex unit, and a plurality of control devices after receiving a reception confirmation signal from a communication partner. And a transmitter for transmitting, as one transmission unit, multiplex control data obtained by multiplexing data for each multiplex unit.

7. Multiple control data is stored for each multiplex unit, and after receiving a reception confirmation signal from the communication partner, multiplex control data obtained by multiplexing multiple control data for each multiplex unit is transmitted as one transmission unit. Communication method.

8. The communication method according to claim 7, wherein a plurality of control data are multiplexed according to information relating a plurality of control data stored as one multiplex unit.